X-COM's cast of alien characters could have looked vastly different. During a postmortem at GDC, X-COM creator Julian Gollop showed some of the alien design mock-ups that were created by one of the game's artists, John Reitze. "This is the visual piece de la resistance of my entire presentation, because it is the only surviving concept work from the whole game," said Gollop. Many of the aliens are variations on the familiar X-COM enemies we all know today. There are different takes on Sectoids and Ethereals, for example. And then there's the giant bunny monster, which you can see in the first row of the image above. Probably for the best that one didn't make the cut.
Another interesting tidbit is that Chryssalids, one of the toughest enemies in X-COM, was something of an accident. "You'll notice that the Chrysallid is right next to the zombie character," said Gollop (third row, far left). "John didn't really imagine them to be connected in any way, but I very quickly had this idea that a Chryssalid would infect your soldiers, and this would turn them into zombies, which would then sprout new Chryssalids, and probably created the most annoying monster in the entire game." We're not sure "annoying" is really the right word – we'd probably go with "terrifying."
During the same panel, Gollop also revealed that X-COM was briefly canceled in 1993, when publisher Microprose was acquired by Spectrum Holobyte. See a larger version of the menagerie in the gallery below.